Method of applying a coating to a concrete surface and product related thereto

Abstract

A method of applying a protective coating to a concrete or concrete-related substrate. The substrate is heated, and then electrostatically-charged coating powder is deposited onto the substrate with the coating powder coalescing into a coherent layer. Then the substrate and the coating are cooled to form the protective layer. The moisture content of the concrete or concrete-related material is sufficiently low so that bubbles or separation does not occur, and sufficiently high so that the electrostatically-charged particles will adhere to the substrate.

Therefore I claim:  
     
         1 . A method of providing a protective coating for a concrete or concrete-related substrate, said method comprising: 
 a) heating said concrete or concrete-related substrate to a temperature sufficiently high to cause moisture in the concrete substrate to turn to a gaseous form to be emitted from the concrete substrate;    b) depositing a layer of an electrostatically-charged coating powder onto a surface area of said concrete or concrete-related substrate to cause said coating powder to coalesce into a coherent layer on the surface of the substrate;    c) cooling said substrate with the layer of coating powder thereon to form into a hardened protective layer on the substrate;    d) said method being characterized in that the moisture content of the concrete or concreterelated substrate is at a sufficiently low level so that during the application of the coating powder bubbles or separation does not occur in the layer of the coating powder coalescing on the substrate, and yet the moisture content of the concrete or concrete-related substrate is sufficiently high so that the electrostatically-charged coating powder adheres to the surface of the concrete or concrete-related substrate.    
     
     
         2 . The method as recited in  claim 1 , wherein said substrate comprises predominately concrete.  
     
     
         3 . The method as recited in  claim 1 , wherein said substrate comprises a composite of concrete and another material.  
     
     
         4 . The method as recited in  claim 1 , wherein said substrate comprises a fiber cement substrate.  
     
     
         5 . The method as recited in  claim 1 , wherein heat is applied to the powder coating and the substrate during the time that the powder coating is on the substrate as a layer to cause said layer to properly form the protective layer on the concrete or concrete-related substrate.  
     
     
         6 . A product made in accordance with the method of  claim 1 , wherein said substrate has a layer of a hardened protective coating thereon, made in accordance with the method of claim  1 .